Fairbanks Annual Summary 2013

The temperature of Fairbanks was somewhat above normal (0.4°F) for 2013 at a mean temperature of 28.1°F. The highest temperature of 92°F was observed on the 25th and 26th of June 2013, close to the summer solstice with over 21.5 hours of sunlight. There were 30 days with temperatures above 80°F, surpassing the long-term mean (1949-present) of twelve days by more than twofold. The lowest temperature of the year was ‑48°F occurring on the 27th January, and there were only six days with minima below ‑40°F; the long term mean is eleven days. With other words, Fairbanks had more hot days than normal in summer and fewer real cold days than normal in winter when compared to the long term, which might be expected by global warming. However these deviations are hardly visible in the mean annual temperature, which is close to normal.

Looking at the monthly data, which are presented in Table 1, it can be clearly seen that on a monthly basis, very large variations were observed. The greatest departure from normal was observed in April, which was an astonishing 14.5°F below the long-term mean of 32.5°F. It was the third coldest April on record for more than 100 years. The lowest temperature for the month was a chilly -21°F on the 11th. That -21°F was a new daily record low, breaking the old record of -17°F set in 1955. Another record low was set the next day with -15°F and broke the 1936 record of -12°F. Then on the 28th the temperature bottomed out at 2°F shattering the 8°F record from way back in 1924. With the exception of the first three days of the month, the temperatures stayed significantly below normal for the rest of the month.

Month

Temperature

Observed (°F)

Normal (°F)

Delta (°F)

January

-2.7

-7.9

5.2

February

-1.4

-1.3

-0.1

March

7.1

11.4

-4.3

April

18.0

32.5

-14.5

May

44.3

49.4

-5.1

June

66.8

60.4

6.4

July

64.3

62.5

1.8

August

59.4

56.1

3.3

September

43.8

44.9

-1.1

October

36.1

24.2

11.9

November

6.1

2.6

3.5

December

-4.5

-4.1

-0.4

On the other side of the coin, there was October with a temperature at 44.0°F, much too warm with a deviation of 11.9°F above normal. The warmest temperature for the month was recorded at 57°F on the 18th and 19th. The max of 51°F on the 28th was a new record, breaking the old high of 44°F from 1959. Overall, this was the third warmest October in 109 years.

Further, the summer season should be mentioned, with all three months having an above normal temperature, with June leading the positive deviations (see Table 1). This brought also many sunny and warm days with on two occasions temperatures above 90°F, unusual for Interior Alaska. In addition, the minimum temperature of 70°F on the 25th was the warmest minimum daily temperature on record for any day in Fairbanks. For Fairbanks, with its long-term climate record, it was the second warmest summer (deviation +3.8°F); only 2004 reported a higher summer temperature. The summer of 2004 was unpleasant insofar that smoke from large wildfires affected strongly the air quality. More than 6 million acres burned. However, while 2013 had a similar temperature regime, the region was much less affected by smoky air. The area burned was above normal (1.3 million acres), the deviation from the long-term mean, some 1 million acres, was not substantial. In Figure 2 the annual course of the temperature and the deviations from the normal are presented, and details for other months can be obtained from this graph.

Precipitation in 2013 was 10.65", very close to the expected value of 10.81".The annual course over the year, both, for the long-term mean and 2013 are presented value in Figure 3 (cumulative daily precipitation).It can be seen from the figure, that sum of the precipitation for the first five months was slightly above normal, thereafter most of the summer was too dry, but late August/early September and November reported above normal values, so that at the end of the year we came very close to the expected value. The snowfall of the year was at 72.0", 12% above the normal value of 63.6". Monthly precipitation data can be seen in Table 2.

Month

Precipitation

Observed (in)

Normal (in)

Delta (in)

Delta %

%

January

0.79

0.58

0.21

36%

136%

February

0.48

0.42

0.06

14%

114%

March

0.26

0.25

0.01

4%

104%

April

0.66

0.31

0.35

113%

213%

May

0.15

0.60

-0.45

-75%

25%

June

0.43

1.37

-0.94

-69%

31%

July

1.01

2.16

-1.15

-53%

47%

August

2.02

1.88

0.14

7%

107%

September

1.74

1.10

0.64

58%

158%

October

0.59

0.83

-0.24

-29%

71%

November

1.74

0.67

1.07

160%

260%

December

0.78

0.64

0.14

22%

122%

The last day of seasonal snow cover was May 11th, much later than normal, and the last frost of the winter came on May 21st, also later than usual. Green up day occurred on the 26th of May, which is latest on record. Growing degree-days totaled 1418 and the growing season was 117 days long, about average. The first frost hit on September 15th, and the snowpack was re-established on November 5th. As might be expected, heating degree-days was 134 below the normal of 13666. Correspondingly, cooling degree-days totaled just 226, 165 more than expected. Mean annual wind speed was 4.2 mph, with lower values in winter, when the semi-permanent inversion decouples the surface conditions from the upper circulation.

On November 13 and 14 a strong storm blowing from the Bering Sea brought warm temperatures and rain to Fairbanks, making driving conditions difficult. Schools were closed. A wind gust of 55 mph was measured at the airport. Falling trees caused widespread power outages.

2013 by the Numbers

Statistic

Value

Mean Annual Temperature

28.1°F

Departure from Normal

0.4°F

Highest Temperature

92°F (25 & 26 June)

Mean Highest Temperature

81.0°F (25 June)

Highs Above 80°F

30 days (Mean since 1949 is 12)

Lowest Temperature

-48°F (27 January)

Mean Lowest Temperature

-41.5°F (27 January)

Lows Below -40°F

6 days (Mean since 1949 is 11)

Total Precipitation

10.65 inches

Departure from Normal

-0.16 inches

Maximum 24hr Precipitation

0.75 inches (11 September)

Total Snowfall

72.0 inches

Departure from Normal

7.0 inches

Maximum 24hr Snowfall

4.8 inches (22 December)

New Record Highs/Lows

6 May

New Record Precipitation/Snowfall

4 June

Heating Degree Days

13532

Departure from Normal

-134

Cooling Degree Days

226

Departure from Normal

165

Growing Degree Days

1418

Average Wind Speed

4.2 mph

End of Seasonal Snow Cover

11 May

Last Freeze

21 May

Greenup Day

26 May

First Freeze

15 September

Establishment of Seasonal Snow Cover

5 November

Wildfire Area Burned

1,320,752 acres

Number of Wildland Fires

612

This information consists of preliminary climatological data compiled by the Alaska Climate Research Center, Geophysical Institute, University of Alaska Fairbanks. For more information on weather and climatology, contact the center at 474-7885 or visit the center web site at http://akclimate.org. Please report any errors to webmaster@akclimate.org.